Unhitched trailers are highly susceptible to theft. Most trailers have a trailer coupler that includes a ball socket for connecting to a corresponding ball hitch on the rear of a truck or pick up. Accordingly, a thief may, for example, connect the ball hitch of his/her towing vehicle to the trailer coupler socket of an unhitched an unattended trailer. The thief may then proceed to drive off with the stolen trailer. While certain devices exist to prevent thieves from stealing unhitched and unattended trailers, most of these conventional devices are time-consuming to use, lack adaptability in engaging with and locking to a plurality of different trailer coupler sockets, and/or easily disengageable/breakable.